Regulation of Vascular Smooth Muscle Growth

性状（由申请方提供）：异常血管平滑肌细胞 血管平滑肌细胞（VSMC）的生长与动脉粥样硬化、高血压和 再狭窄本提案的长期目标是描述 协调调节介导VSMC生长的信号转导级联 并确定生长因子对这些级联的差异调节 和肥大激动剂。VSMC具有肥大和增殖的能力， 增长尽管G蛋白和G蛋白激活了无数的信号通路， 偶联受体和受体酪氨酸激酶，很少有人知道如何 这些信号被整合，并且是否共同的受体近端信号传导 控制点使增长和迁移同步。非受体酪氨酸 激酶PYK 2将G蛋白和生长因子受体连接到下游 信号级联。新的初步数据表明，PYK 2下调， 反义寡核苷酸阻断血管紧张素II（Ang II）和血小板衍生的 生长因子（PDGF）诱导的蛋白质和DNA合成， 抑制粘着斑激酶（FAK）、p38和ERK 1/2 MAP激酶， 以及磷脂酰肌醇3-激酶/Akt/p70 S6激酶途径。的假设 PYK 2代表一个近端信号事件， 整合（链接）来自Gq偶联受体和受体酪氨酸的信号 激酶来控制参与VSMC生长的下游信号级联， 迁移三个具体目标将检验这一假设： 反义寡核苷酸和腺病毒构建体将用于 确定PYK 2是否是蛋白质翻译起始、细胞 周期进展和VSMC迁移。在目标2中，使用PYK 2反义核酸的实验 ERK 1/2、p38和PI 3 K通路的药理学抑制剂将决定 细胞信号级联反应是PYK 2激活的下游， 血管紧张素II和血小板衍生生长因子。在目标3中，显性阴性PYK 2腺病毒构建体或 PYK 2反义核酸将用于体内阻断VSMC肥大和增殖 使用小鼠颈动脉损伤模型。这些结果可能会提供新的见解 协调VSMC生长调节，并可能确定的可行性， 靶向近端信号传导中间体作为潜在的治疗剂 血管疾病的治疗策略。

DESCRIPTION (provided by the applicant): Aberrant vascular smooth muscle cell (VSMC) growth has been implicated in atherosclerosis, hypertension and restenosis. The long-term goal of this proposal is to characterize the coordinated regulation of signal transduction cascades that mediate VSMC growth and to determine differential regulation of these cascades by growth factors and hypertrophic agonists. VSMC are capable of hypertrophic and proliferative growth. Although a myriad of signaling pathways are activated by both G-protein coupled receptors and receptor tyrosine kinases, little is known about how these signals are integrated and whether common receptor-proximal signaling control points synchronize growth and migration. The nonreceptor, tyrosine kinase PYK2 links G-protein- and growth factor receptors to downstream signaling cascades. New preliminary data indicate that PYK2 downregulation by antisense oligonucleotides blocks Angiotensin II- (Ang II) and platelet derived growth factor (PDGF)-induced protein and DNA synthesis that was associated with inhibition of focal adhesion kinase (FAK), the p38 and ERK1/2 MAP kinases, as well the phosphatidylinositol 3-kinase/Akt/p70S6 kinase pathway. The hypothesis of the current proposal is that PYK2 represents a proximal signaling event that integrates (links) signals from both Gq-coupled receptors and receptor tyrosine kinases to control downstream signaling cascades involved in VSMC growth and migration. Three specific aims will test this hypothesis: In Aim 1, studies with antisense oligonucleotides and adenoviral constructs will be used to determine whether PYK2 is required for protein translation initiation, cell cycle progression and VSMC migration. In Aim 2, experiments with PYK2 antisense and pharmacological inhibitors of ERK1/2, p38 and PI3K pathways will determine which cellular signaling cascades are downstream of PYK2 activation in response to Ang II and PDGF. In Aim 3, dominant negative PYK2 adenoviral constructs or PYK2 antisense will be used to block VSMC hypertrophy and proliferation in vivo using a mouse carotid artery injury model. The results may provide new insight coordinated VSMC growth regulation and may determine the feasibility of targeting the proximal signaling intermediates as potential therapeutic strategies for vascular disease.